Traveler was launched on September 21, 2013, after two years of hard work and waiting. The flight ended in an explosion at T+3.5 seconds. Most parts of the rocket were recovered, and some can be reused. Luckily, enough of the motor was intact to piece together the cause of the explosion. This update will cover pre-launch operations, the launch itself, and future plans.
To launch Traveler, we attended the annual BALLS rocketry event in Black Rock, Nevada. The playa, as the dry lake bed is called, is one of the flattest places in the world. It is a 9-10 hour drive from LA, and frequently has harsh weather such as sandstorms. RPL goes to Black Rock once or twice a year to launch our largest vehicles; smaller ones are launched at the Mojave Test Area.
Final assembly of Traveler went fairly smoothly, with successful tests of recovery deployment and avionics transmissions. Everything appeared ready as we packed the trailer on Wednesday.
The scene inside the trailer.
"Area 52" departing.
In a very rare event for RPL, the trailer ended up leaving earlier than scheduled, at 2300 Wednesday. Brake trouble necessitated a stop in Sacramento for maintenance, so the total trip time for the trailer amounted to about 21 hours, justifying why we like to leave with time to spare.
On Friday morning, we drove the trailer out about one mile from the flight line, unloaded the tower, and parked the trailer an additional 300 feet away. Weather in the morning was nice, but heavy winds and sandstorms developed in the afternoon as we took the final steps to prepare the rocket for flight.
The avionics package, minus the outer tube.
The tower area.
Our new launch monitoring software.
It was obvious through most of the afternoon that a launch could not be attempted -- we couldn't even keep the trailer door open for more than a few seconds before the air inside would be filled with dust. We took the opportunity to let everyone sign the rocket:
The FAA had established Temporary Flight Restrictions in the area from 1700-1900 that day, which meant we needed to launch before 1845 to be clear of the airspace by 1900 (something we didn't learn until that evening). When the weather became tolerable at about 1800, we finished integrating the rocket and carried it over to the launch tower. By the time it was vertical and people had taken pictures, we were within a few minutes of 1845, meaning we couldn't launch that day. It was disappointing, but we knew we had additional launch windows the next two days, so we lowered the tower and brought the rocket back to the trailer. The winds were still bad at that point, making the porta potties back at the flight line vibrate like washing machines!
Positioning the tower for the first launch attempt.
The next day, we spent the morning and early afternoon charging batteries and generally being stuck inside the trailer. There was some light rain, which reduced the dust levels. The rain meant that the sedans had to leave the playa and return to Gerlach. Some cars were subsequently unable to return to the playa because of muddy spots at the playa entrances, and watched the launch from Gerlach or an adjacent mountain.
Panorama of the launch site.
Integration went smoothly once again, and Traveler was vertical in the tower at 1710. The weather was still improving, but we had to wait for the cloud cover to dissipate somewhat. Once the clouds were cooperating, a train was spotted on the tracks next to the playa, and we waited about 10 minutes for it to go by. The ignition signal was finally sent by Alec at 1807. The composite igniter took a few dramatic seconds to ignite the whole motor.
Traveler soared almost straight up, obscuring the view of the rocket from the trailer. After 3.5 seconds of flight, at approximately 4000 feet, the smoke trail became abruptly larger and separated into several pieces, followed in a fraction of a second by the unmistakable sound of a solid rocket motor catastrophically failing. The pieces of the rocket arced over, with what was left of the motor still spewing fire from both ends as it cartwheeled. The team split up to run and drive out to the pieces. The nosecone landed the closest, bouncing on the titanium tip; other parts drifted farther, like the motor (which made a decent-sized crater) and the parachute (which went several miles).
The nosecone, largely intact.
We brought the pieces back to the trailer to see what went wrong. The debris included two nearly-intact grains that had been extinguished when the motor lost pressure. They exhibited evidence of backside burning, meaning that the propellant in contact with the casting tube had not been properly inhibited and had started to burn, increasing the chamber pressure. If this had happened on many grains, the pressure increase could have been enough to blow the case; it's also possible that some grains lost chunks of propellant which clogged the nozzle.
A grain with obvious evidence of backside burning.
We view this flight primarily as a chance to learn. We were prepared for the possibility of a failure; after all, Traveler's motto is "space or nothing!" We were ironically reminded of this slogan when it was exposed, written in sharpie, on the outside of the motor case under the tip-to-tip layers -- not a place we ever expected to see again.
As Jordan said:
"We didn't reach our end goal, but we have still accomplished another step on the way. We built a spaceshot, had it on the pad armed and fueled, and fired it. No other group of students has gotten anywhere close to that. I'm excited we have gotten this far - we had issues - and we'll work through them and will be back soon enough.
"This series of event that led to this moment - including the concept and initial lab development, all the prior projects which tested technologies for Traveler, the lengthy paperwork process, along with the design, build, and rebuilds of it - have spanned nearly a decade. The number of people who have been involved is far too many to list here.
"For the flight crew - who this past weekend dealt with the worst that Black Rock could offer, part of which locked themselves in our trailer for 7 hours waiting for storms to pass, part of which was stranded by mud blocking the playa entrances, and the countless other oddities that happen out there - you're amazing.
"Thank you and congratulations to everyone who has helped make this happen."
Traveler's BLM permit included backup launch opportunities 2 and 4 weeks after BALLS. We wanted to use the 4-week window to launch Traveler 2, a rebuilt version of Traveler with some enhancements, but were not able to finish it in time -- and the government shutdown prevented us from using the playa. We'll post details about future plans as they become available.
Finally, thanks to a variety of members for providing pictures that went into this update. You can view them on
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Flight on!